A ZSH script to rebuild my macos routing table for whichever network I am on so that I can run my FortiClient VPN permanently without having all traffic tunnelled up the utun1 interface by the VPN config

rerouter.sh

#!/bin/zsh

usage() {
  print "Usage: sudo rerouter -n network"
  exit 1
}

while getopts ':n:' arg; do
  case $arg in
    n)
      NET=$OPTARG
      ;;
    \?)
      print "Invalid option -$OPTARG" >&2
      exit 1
      ;;
    :)
      print "Option -$OPTARG requires an argument." >&2
      exit 1
      ;;
  esac
done

if [ "$NET" = "office" ]; then
  DEFAULTGW="10.1.42.65"
elif [ "$NET" = "home" ]; then
  DEFAULTGW="192.168.0.1"
elif [ "$NET" = "hotspot" ]; then
  DEFAULTGW="0.0.0.0"
else
  print "Sorry. Unrecognised network."
  exit 1
fi

print "Rebuilding routing table for $NET."
sudo route delete default
sudo route add default $DEFAULTGW
sudo route -n add -net 192.168.0.0/24 172.27.1.100
sudo route -n add -net 192.168.101.0/24 172.27.1.100
sudo route -n add -net 192.168.102.0/24 172.27.1.100